Deep-Brain Stimulation May Help Hard-to-Treat Anorexics

Deep-brain stimulation, a technique
that has shown promise in treating mental disorders as well as
Parkinson’s disease, may also help severe and enduring anorexia,
a small, early-stage study suggests.

The main goal of the six-patient study was to see whether
the pacemaker-like device, made by Medtronic Inc. (MDT), could be
implanted safely. While one patient suffered a seizure two weeks
after the procedure, at least half of those who received the
implant showed improvements in mood and body mass, according to
the findings published today in The Lancet medical journal.

The findings add to potential uses of deep-brain
stimulation, which has been shown to be effective in epilepsy,
chronic pain and obsessive-compulsive disorder. Medtronic’s
Activa device is approved in the U.S. and Europe to treat
Parkinson’s and tremors. As many as 20 percent of anorexia
patients don’t respond to therapy and as many as 11 percent of
anorexics die of the condition, the researchers said.

“New effective treatments for these patients are sorely
needed,” Janet Treasure and Ulrike Schmidt, professors at
King’s College London’s Institute of Psychiatry, wrote in a
comment accompanying the study. “The findings of this proof-of-
concept study are promising and will give hope to patients with
especially pernicious forms of the disorder and their
families.”

Electrical Currents

In deep-brain stimulation, a battery-operated device shoots
electrical currents into a targeted area of the brain, similar
to pacemakers used to manage heart rhythms. The approach, which
is minimally invasive and completely reversible, has been used
for more than 25 years to regulate dysfunctional brain circuits,
according to the study.

Scientists at the Krembil Neuroscience Centre and
University Health Network in Canada used magnetic resonance
imaging to identify an area of the brain that has been used for
deep-brain stimulation in patients with depression. Electrodes
were then implanted into that area in each patient and connected
to a pulse generator, which was inserted under the skin.

The researchers activated the device 10 days after the
surgery and measured changes in patients’ mood and anxiety
levels to identify the correct level of stimulation, according
to the study. Changes in mood and body mass index were measured
with standardized tests.

Improved Mood

“The finding of improvements in mood and anxiety in
patients who were still underweight is especially striking, in
view of the well-known poor response of underweight patients to
conventional pharmacotherapies or psychotherapies,” Andres
Lozano, one of the researchers, said in a statement.

The six female patients were between 24 and 57 and had been
suffering from anorexia for between four and 37 years. The
patient who had a seizure two weeks after the procedure had her
device shut off and reactivated a week later, with no
recurrence. The seizure was probably linked to a metabolic
disorder she had as a result of her anorexia, the researchers
said. Other adverse events included a panic attack during
surgery, nausea and pain, they said.

Minneapolis-based Medtronic and St. Jude Medical Inc. of
Saint Paul, Minnesota, are among companies that market
implantable devices for deep-brain stimulation treatment of
neurological illnesses.